Plastic closure for containers

ABSTRACT

A plastic closure for containers comprising a top provided with depending inner and outer skirts, said skirts having facing surfaces which non-sealingly contact surfaces of a bottle neck adjacent its edge, said inner skirt merging into an annular radially projecting sealing member surrounding and integral with a concavo-convex closure web, said sealing member engaging a restricted area of the inner surface of the bottle neck. The closure may be removed by use of a cap lifter or the top of the closure may be provided with weakening means which divide the top into an outer and an inner ring, the outer ring being severed from the inner ring in one segment of the top and the top having an unweakened area opposite the severed segment which connects the outer ring to the rest of the closure for lifting the closure from the bottle.

United States Patent Bly [ 51 June 27, 1972 PLASTIC CLOSURE FOR CONTAINERS Appl. No.: 109,210

US. Cl. ..2l5/4l, 215/42, 215/46 A ..B65d 41/22, B65d 41/32 Field of Search ..215/41, 42, 46 A References Cited UNITED STATES PATENTS 3,343,700 9/1967 Heubl..... ...215/41 3,462,035 8/1969 Grussen ..215/42 Primary Examiner-George T. Hall Attorney-Bertha L. MacGregor [57] ABSTRACT A plastic closure for containers comprising a top provided with depending inner and outer skirts, said skirts having facing surfaces which non-sealingly contact surfaces of a bottle neck adjacent its edge, said inner skirt merging into an annular radially projecting sealing member surrounding and integral with a concave-convex closure web, said sealing member engaging a restricted area of the inner surface of the bottle neck. The closure may be removed by use of a cap lifter or the top of the closure may be provided with weakening means which divide the top into an outer and an inner ring, the outer ring being severed from the inner ring in one segment of the top and the top having an unweakened area opposite the severed segment which connects the outer ring to the rest of the closure for lifting the closure from the bottle.

6 Clalms, 9 Drawing Figures PATENTEnJum I372 3. 672,527

INVENTOR.

RAY E. BLY

ATTORNEY PLASTIC CLOSURE FOR CONTAINERS This invention relates to plastic caps for bottles, and particularly to plastic caps for sealing beer bottles or other beverage containing bottles. I

An object of the invention is to provide removable closures for bottles which maintain the contents in their intended conditions, under pressure or otherwise, which are easily removable by a manual pull-off operation or by the use of a cap lifter.

Another object is to provide a removable closure which may be replaced on a bottle into bottle sealing position for preserving bottle contents in their intended condition.

Another object is to provide closure means having bottle contacting surfaces which serve to fully cover and protect the bottle neck to which they are applied but without sealing engagement therewith, and having sealing means engaging only a restricted area of the inner surface of the bottle neck for sealingly closing the bottle. The closure means of this invention thus facilitates easy and quick removal of the cap while providing sealing engagement efficient to maintain the bottle contents in intended condition.

In the drawings:

FIG. 1 is a top plan view on an enlarged scale of a plastic bottle cap of the pull-off type embodying my invention.

FIG. 2 is a vertical sectional view in the plane of the line 2-- 2 of FIG. 1.

FIG. 3 is a vertical sectional view of a portion of the cap in the plane ofthe line 3-3 of FIG. 1.

FIG. 4 is a top plan view on an enlarged scale of a modified plastic cap of the pull-off type embodying my invention.

FIG. 5 is a vertical sectional view of a portion of the cap in the plane of the line 5-5 of FIG. 4.

FIG. 6 is an elevational side view of the cap of FIGS. 1 or 4 as it appears when the cap has been partially lifted from a bottle the upper part of which is shown in side elevation and partly in section.

FIG. 7 is a top plan view on an enlarged scale of a plastic bottle cap embodying my invention, designed for removal from a bottle by a conventional cap lifter.

FIG. 8 is a vertical sectional view in the plane of the line 8- 8 of FIG. 7.

FIG. 9 is a vertical sectional view of the cap of FIG. 8 as it appears when in sealing position on a bottle, the upper end of which is shown in side elevation and partly in vertical section.

The invention as shown in FIGS. 1-6 is embodied in plastic caps of the pull-off type, and as shown in FIGS. 7-9 is embodied in plastic caps designed for removal by use of a conventional cap lifter or bottle opener.

Referring to FIGS. 1-6, the cap 10 comprises a top having an upper exposed surface 11 and a lower surface 12 for contacting the edge of the neck of a bottle, both surfaces being substantially flat and parallel to each other. The top is integral with a downturned peripheral skirt depending from the outer circumferential edge of the top, said skirt having an exposed outer surface 13 and inner surface14. The top also is integral with an inner downturned skirt having substantially vertical annular surfaces and 16. The skirt surfaces 14 and 15 are bottle contacting surfaces but are not sealing surfaces. The inner skirt surfaces 15 and 16 merge into a bottle closure web 17 having a lower convex surface 18 and an upper concave surface 19. The inner skirt surface 15 is shorter in vertical dimension than the surface 16 and merges into the web 17 by an annular thickened or projecting sealing member 20 between the surfaces 15 and 18.

The member 20 has sealing contact with the inner surface of the neck 21 of the bottle 22 and constitutes the only part of the cap which has sealing engagement with the bottle as distinguished from the non-sealing contact of other parts of the cap with the bottle.

The outer skirt surfaces 13, 14 serve to cover and protect the bottle neck 21 without sealing engagement therewith. The lower circumferential edge of the cap surface 14 is slightly spaced from the outer surface of the neck 21 for the purpose of facilitating manual removal of the cap. Likewise, the sur face 15 of the inner skirt engages the inner surface of the bottle neck without sealing engagement therewith, the sealing pressure being confined to that exerted by the radially projecting thickened annular member 20 between the inner skirt and the closure web 17.

Referring now to the means which permit manual pulling off" of the cap from the bottle 22, as shown in FIGS. 1-3, the flat top is provided with weakening means which divide the top into an outer flat pull ring 25 and an inner ring 26, the latter being designed to remain in its integral relationship relatively to the depending skirt defined by the surfaces 15, 16 and the closure web 17. The weakening means of FIGS. 1-3 comprises an inverted V-shaped notch 30 which extends in the arc of a circle at opposite sides of the cap top, from the bottom surface 12 nearly to the upper surface 11 as shown in FIG. 3. The two notched areas 30 extend from an unweakened or unnotched area 31 (FIG. 1) and meet to form a severed portion in which the notch 30 is extended upwardly by a slit 32 as shown in FIGS. 1 and 2. The slit portion 32 is diametrically opposite the unweakened area 31 of the cap top. The weakening means 30 and 32 thus divide the top of the cap into the outer ring 25 and inner ring 26 except in the area designated 31 in FIG. 1, the slit portion being adjacent that part of the outer ring 25 marked Lift".

In the modification of the plastic cap shown in FIGS. 4 and 5, the top is weakened by a broken arcuate line of slits 33 and severed by a longer slit 34, the latter being located adjacent that portion of the outer ring 25 designated Lift". The slits 33 may extend through or nearly to the upper surface 11 of the top of the cap, which is the upper surface of the outer ring 25 and inner ring 26, except in the area designated 35 (FIG. 4) diametrically opposite the Lift area and the slit 34.

As shown in FIG. 6, which portrays the pull-off" removal of the cap from the bottle neck 21, the user manually grasps the peripheral skirt adjacent the area marked Lift" on the outer ring 25, being that portion easily separable from the inner ring 26 due to the slit 32 of FIGS. 1-3 or the slit 34 of FIGS. 4-5, and by a lifting motion tears the ring 25 from the ring 26 excepting in the area 31 (FIG. 1) or 35 (FIG. 4). Said areas 31 and 35 remain in integral relationship with the rest of the cap, namely, the depending wall l5-l6 and closure web 17 with sealing memberv 20. Continued pull on the ring 25 transmitted to the areas 31 or 35 with attached parts of the cap results in lifting the skirt 13-14 beneath the areas 31 or 35 breaking the sealing engagement between sealing member 20 at the left of FIG. 6, and gradually toward the right of the figure until the entire cap is free.

If it is desired to replace the cap for resealing the bottle, the inner ring 26 with attached depending skirt 15-16 and closure web 17 is replaced on the neck 21 of the bottle, and the web 17 is depressed into sealing engagement with the inner surface of the neck.

FIGS. 7, 8 and 9 illustrate a plastic cap 40 such as the cap 10 heretofore described, but devoid of weakening means or severing means in the top for pull-off" of the cap by the user. This modification is designed for removal by use of a cap lifter. Except for the absence of the weakening and severing means heretofore described, the construction of the cap shown in FIGS. 7-9 comprises the parts heretofore described, namely, the top with upper and lower surfaces 11, 12; outer depending peripheral skirt with surfaces l3, l4; inner depending skirt with surfaces 15, 16; web 17 defined by convex surface 18 and concave surface 19; and bottle engaging sealing member 20 extending angularly around the web and merging into surfaces 15 and 18.

As shown in FIG. 9, a small annular space 41 exists between the inner surface 14 of the outer skirt of the cap and the bottle neck 21 which facilitates the use of a cap lifter for engaging the outer skirt for lifting of the cap from the bottle 22. This space also exists between the peripheral skirt and bottle shown in FIGS. 1-6, where it facilitates manual grasping of the skirt for the pull-01f removal of the cap.

The cap is applied to a bottle by use of a tool having a head complemental to the surface 19 of the web 1-7 for depressing the web and momentarily deforming the cap in the outer annular area including the sealing member 20 to reduce the diameter of the inner skirt -16 and allow the integral inner skirt and web to slip into the bottle neck. Upon withdrawal of the tool head, the sealing member moves into sealing engagement with the inner surface of the bottle as shown in FIGS. 6 and 9. The bottle neck 21 is fully protected by the cap surface 12, and the facing skirt surfaces 14 and 15 which contact the neck, and the bottle contents are maintained in their intended condition, under pressure or otherwise, by the sealing means 20 engaging the inner surface of the bottle neck, while permitting removal and replacement of the cap. The cap of FIGS. l-6 may be removed by the pull-off method or by use of a cap lifter, whereas the cap of FIGS. 7-9 is designed for removal by means of a cap lifter.

The plastic material of which the closure device is made may be synthetic resin such as polyethylene or other suitable plastic. The closure device protects the product within the container and also serves as a relief valve in the event that internal bottle pressures increase excessively, thereby preventing an explosion of the container and possible injury to the user. Glass bottles are tested to withstand internal pressures of l-l50 psi whereas the plastic cap of my invention is designed to withstand pressures of 50-60 psi within the container on which it is mounted which is ample for preserving the quality and condition of the bottle contents while permitting relief in the event of excessive pressure within the container. The domed web portion 17 surrounded by the sealing member 20 is so configured that small pressure increases within the bottle result in an expansion of the sealing surface against the container thus providing additional sealing capability.

I claim:

1. A plastic closure for containers comprising a. a top overlying the edge of a bottle neck,

b. an outer and an inner skirt radially spaced apart depending from the top and having annular surfaces facing the outer and inner surfaces of the bottle neck in non-sealing contact,

0. a closure web having an upper concave surface and a lower convex surface merging with the lower edge of the inner skirt, and

d. an annular sealing member surrounding the web and projecting radially from the junction of the web and inner skirt into sealing engagement with the inner surface ofthe bottle neck,

external pressure on the web causing deformation of the web and diminished diameter of the sealing member for positioning it in sealing engagement in the bottle neck, and limited internal pressure on the web causing expansion of the diameter of the annular sealing member and increased sealing engagement in the bottle neck.

2. The closure defined by claim 1, in which the lower edge of the outer skirt is slightly spaced from the bottle neck for engagement by a cap lifter for removal from the bottle.

3. A plastic closure for containers comprising a. a top overlying the edge of a bottle neck, said top having a slit extending in arcuate directions through a segment of the top, and weakening means extending in arcuate directions from the slit to an unweakened area opposite the slit, dividing the top into an outer annular ring and an inner annular ring connected together in said unweakened area,

b. an outer and an inner skirt radially spaced apart depending from the top and having annular surfaces facing the outer and inner surfaces of the bottle neck in non-sealin g contact,

c. a closure web having an upper concave surface and a lower convex surface merging with the lower edge of the inner skirt, and d. an annular sealing member surrounding the web and projecting radially from the junction of the web and inner skirt into sealing engagement with the inner surface of the bottle neck,

said closure being removable from the bottle neck by manually grasping the outer skirt adjacent the slit in the top, pulling the outer skirt and outer ring portion of the top upwardly to separate them from the inner ring to the weakening means, and continuing the pulling on the outer ring and connected portion of the inner ring to withdraw the inner skirt sealing member and web from the bottle neck.

4. The closure defined by claim 3, in which the weakening means is an annularly extending inverted V-shaped groove separating the inner and outer rings of the top, said groove extending from the lower surface of the top to near the upper surface of the top.

5. The closure defined by claim 3, in which the weakening means is an annularly extending broken line of slits extending through the top.

6. The closure defined by claim 3, in which the lower edge of the outer skirt is slightly spaced from the bottle neck for engagement by a cap lifter for removal from the bottle as an alternative to removal by the pull-off means. 

1. A plastic closure for containers comprising a. a top overlying the edge of a bottle neck, b. an outer and an inner skirt radially spaced apart depending from the top and having annular surfaces facing the outer and inner surfaces of the bottle neck in non-sealing contact, c. a closure web having an upper concave surface and a lower convex surface merging with the lower edge of the inner skirt, and d. an annular sealing member surrounding the web and projecting radially from the junction of the web and inner skirt into sealing engagement with the inner surface of the bottle neck, external pressure on the web causing deformation of the web and diminished diameter of the sealing member for positioning it in sealing engagement in the bottle neck, and limited internal pressure on the web causing expansion of the diameter of the annular sealing member and increased sealing engagement in the bottle neck.
 2. The closure defined by claim 1, in which the lower edge of the outer skirt is slightly spaced from the bottle neck for engagement by a cap lifter for removal from the bottle.
 3. A plastic closure for containers comprising a. a top overlying the edge of a bottle neck, said top having a slit extending in arcuate directions through a segment of the top, and weakening means extending in arcuate directions from the slit to an unweakened area opposite the slit, dividing the top into an outer annular ring and an inner annular ring connected together in said unweakened area, b. an outer and an inner skirt radially spaced apart depending from the top and having annular surfaces facing the outer and inner surfaces of the bottle neck in non-sealing contact, c. a closure web having an upper concave surface and a lower convex surface merging with the lower edge of the inner skirt, and d. an annular sealing member surrounding the web and projecting radially from the junction of the web and inner skirt into sealing engagement with the inner surface of the bottle neck, said closure being removable from the bottle neck by manually grasping the outer skirt adjacent the slit in the top, pulling the outer skirt and outer ring portion of the top upwardly to separate them from the inner ring to the weakening means, and continuing the pulling on the outer ring and connected portion of the inner ring to withdraw the inner skirt sealing member and web from the bottle neck.
 4. The closure defined by claim 3, in which the weakening means is an annularly extending inverted V-shaped groove separating the inner and outer rings of the top, said groove extending from the lower surface of the top to near the upper surface of the top.
 5. The closure defined by claim 3, in which the weakening means is an annularly extending broken line of slits extending through the top.
 6. The closure defined by claim 3, in which the lower edge of the outer skirt is slightly spaced from the bottle neck for engagement by a cap lifter for removal from the bottle as an alternative to removal by the pull-off means. 